stehljk



Aug) 30, 1927. 1,640,473

R. F. STEHLIK I 1 IMPULSE SENDER Original Filed un 9. 1924 5 Sheets-She2 *Inusn m:

Bub 131 221 F. 57521 71 5 1,640,47 30 R. F. STEHLIK 3 IMPULSE SENDE'ROriginal Filed June 9, 1924 5 Sheets-Sheet 3 frz Y 5% 4/ Inuarr mu-'Ending uh F. SEEM:

1927- R. F. STEHLIK IMPULSE SENDER Original Filed Jun 9. 1924 5Sheets-Sheet 5 WW 11m NNN Eur/7:2 h E 52511111:-

Patented Aug. 30, 1927. I

UNITED STATES PATENT errici i RUDOLPH IF. STEI-ILIK', OF CHICAGO,ILLINQIS, ASSIGNOB, BY MESNE ASSIGNMENTS, TO AUTOMATIC ELECTRIC INC OFCHICAGO, ILLINOIFa, A CORPORATION OF DELA- WARE.

Application filed June 9, 1824, Serial No. 718,683. Renewed December 29,1926.

The present invention relates in general to impulse senders but isconcerned more particularly with impulse senders used in telephonesystems and more especially those which employ a progressively movableswitch mechanism to count the impulses as they are sent or transmitted.

The main object is the production of new and improved circuitarrangements whereby the counting switch of a sender is provided with aplurality of normal positions to avoid the necessity of rotating overall the remain ing positions when a series of impulses comprising only asmall number of impulses is transmitted. For example, impulse sendersare ordinaily designed to send out a maximum ot ten impulses and have,in addition to one normal position and one pick-up position, ten sendingpositions. Now in case a series of impulses comprising only three im pules, for example, is transn'iitted, it is necessary, at the end of theseries,to advance the sending switch through its remaining sevenpositions before its normal position is reached.

In order to cut down this large amount of wasted movement, which is thecause of a large amount of wear and tear on the switch e-chanism itsielfand is also the cause of wasted time between successive serles of1mpulses, a novel circuit arrangement has been provided which allows fora second normal position at which the sending mechanism may be stoppedat a halt way point. Now, a in order to prevent the sending mechanismfrom being out of step when it is started from this second normalposition, it is provided with a second control wiper which is:uitomatically connected up and used instead 4 oi? the normal controlwiper when the switch is started from its intermediate normal position.

Although senders of the above type may be used for any one of a numberof purposes and in connection with any one of a number of devices, ithas been chosen to illust "ate the sender in connection with a socalleddirector which is employed in a multi-o'liice automatic telephone systemprimarily to promote trunking cfficieney by permitting calls to alloflices in the same locality to be handled over the same group of trunksregardless of their numerical desig nation. l eee directors are used toregister n: a number to retrans mit the proper code to trunk the call tothe desired oiiice in accordance with the most ecoi'iomical trunkingarrangement and to register and retransmit unchanged the tour subscriberdigits of a number.

Although the director as a whole does not form any part oi thisinvention, but is used merely toillustrate one use for the new andimproved sender, it is, nevertheless, an object of the invention tocombine the new and improved sender with the remaining part of thedirector so that the'entire director functions as a unitaryorganization.

Referring now to the drawings comprising Figs. 15, inclusive, they showby means of the usual circuit diagrams, a suflicient amount 01 apparatusin a system embodying the principlesof invention to enable the inventionto be understood and its utility appreciated.

Fig. 1 shows the substation A of which the associated line terminates atthe exchange in the line switch C, which has accessthrough the trunkcircuitTC to the first selector 1). This drawing shows also the directorselector DS.

Figs. 2-5, inclusive, show a director which is one of the groupaccessible to the director selector DS, Fig. 1. The portion of thedirector shown in Fig. 2 comprises the se quence switches S and S whichare used respectively to control the registrationandtheretransn'iission0t the impulses; the portion of the director shown inFig. 3 comprises the new and improved sender which sends out the correctnumber of impulses for each digit, starting from either of its twonormal positions impartially; the portion of the director shown in Fig.4L comprises the oflice register OR and the intermediate distribut ingtrame IDF by means of which the oliice codes may be readily changed; andthe portion otthe director shown in Fig. 5 comprises the digit registersDR DR inclusive, which are used to register the four subscriber digitsin a number.

Regarding theequipment involved in the present disclosure, it may bestated that the substation A, Fig. l', is of the usual automatic type;the line switch C, Fig. 1., together with the director selector DS, the"Witch S, Fig. 2, and the sending 3, is of the well in? wu I '7 \ckrota. y 9e or witch in which the red in ftorward directit.

are advanced upon the back stroke of the stepping magnet rather thanupon the front stroke; the selector D, Fig. 1, together with the ofiiceregister'OR, Fig. 4, is an automatic switch of the well known verticaland rotary type and its bank contacts are accordingly arranged inhorizontal rows or levels; and

the sequenceswitch S, Fig. 2, together with the digit registers DR DRflinclusive, Fig. 5, is of a simple type of switch having wipers which areadvanced in a forward direction by the stepping magnet 105 and whicharerestored to normal by the release magnet 106 under the control of thecontacts 107 which close when the wipers 108 and 109 are first moved"from their normal position and which open again when the wipers aresubsequently restored to their normal position.

A detailed description of the operation of the apparatus shown will nowbe given. For this purpose it will be assumed that the subscriber atsubstation A, desiring to make a call, removes his receiver. \Vhen thisoccurs, a circuit is closed over line conductors 11 and 12 for linerelay of the line switch C, whereupon line relay 15 energizes; placesground 'on private normal conductor 13 at armature 23, thereby makingthe calling line usy imn'iediately and closing a circuit throughswitching relay 14 and stepping magnet 16 in series; and at armature 24connects test wiper 21 to the junction of switching relay 14 andstepping magnet 16.

From this point the operation depends upon whether the trunk terminatingin the bank cont-acts upon which the wipers of the line switch arestanding is busy or idle. Assuining first that the trunk is idle,switching relay 14 energizes immediately, seizing the trunk.

Assun'iingnow that the trunk upon which the wipers of the line switchare standing is busy, switching relay 14 is short circuited by "heground potential encountered on the busy test contact by test wiper 21and does not energize. interrupts its own circuit, is operated from thissame ground potential through test wiper 21'and advances the wipers 22,inclusive, step by step in search of an idle trunk. Vhen an idle trunkis reached, which trunkyit will be assumed,,is the one comprisingconductors 27, inclusive, there is no ground potential encountered uponthe test contact thereof 'bytest wiper 21, and switching relay 14, beingno longer short circuited, energizes. Stepping magnet 16, however, doesnot energize at this time, on account of the high resistance ofswitching relay 14. Upon energizing,switching relay 14 disconnects testwiper 21 from the junction of its own winding and that of steppingmagnet 16 and connects it to thegrounded private normal conductor 13at'armature 18,

Stepping magnet 16, which thereby making the seized trunk busyimmediately, and at armatures 17 and 19 disconnects the line conductors11 and 12 from the windings of line relay 15 and ground, and extendsthem way of wipers 20 and 22, the bank contacts upon which theyarestanding, conductors 25 and 27, and the resting contacts and armaturesand 41 to the windings oi" the double wound line relay 31 of the trunkcircuit TC. Line relay 31 now energizes over the calling line and closesat armature 34 a circuit for release relay 32, whereupon release relay32 energizes and places ground upon release trunk conductor 26, atarmature 36 thereby completing the usual holding circuit for switchingrelay 14 of the line switch C before the slow acting linerelay 15 hashad time to dcenergize.

As a further result of the energization of release relay 32, it closesat armature 37 a circuit for switching relay 81 and stepping magnet 82ot' the director selector DS in series, and at armature 38 connects testwiper 89 to the junction of the said switching relay and steppingmagnet. Accordingly, the director selector DS operates in the samemanner as already explained in connection with the line switch G toselect an idle director. Assuming that the director reached by 'way ofconductors 91-94, inclusive, is the first one found to be idle, thewipers 87 90, inclusive, are rotated and stopped in engagement with thebank contacts in which the said conductors 9194, inclusive, terminate,whereupon switching relay 81 energizcsand grounr 5 test wiper 89 atarmature 85, thereby making the seized director busy ii'i'unediately. Asa further result of the energization of switching relay 81, it preparesthe operating and switching circuit at armature 86; and at armatures 83and 84 connects up wipers 87 and 88, thereby placing a closed bridgeacross conductors 42 and 44 of the selector D. This closed bridgeineludes conductors 91 and 92, and armature 208 and its resting contactof relay 202, Fig. 3, and contacts 233 of the sending switch SS inmultiple. Responsive to the closure ofthis bridge, line relay 51 of theselector D energizes and closes a circuit for release relay 52 atarmature 62, whereupon release relay 52 energizes also, preparing theselec'tor for-operation in the usual manner.

In'the director, the holding relay 201. Fig.

3, is energized over test conductor 93 responsive to the latter beinggrounded through wiper 89 of the director selector- DS, and at armatures206 and 207 opens the two release circuits of the director.

hen the calling subscriber manipulates his calling device in accordancewith the first digit in the dcsirednumber, the circuit of line relay 31of the trunk circuit TC is opened a corresponding number of times.

Upon each of the resulting dcenergizacions of line relay 31, it closesat armature 85 a circuit. for the vertical magnet. 301 of the oiiiceregister OR, Fig. 4, as follows: From ground by way of the restingcontact and armature .35 ot the line relay 31, armature 80 and workingcontact wviper 90, con doctor 94-, slow acting series relay 101, Fig. 2,wiper 109 01? the sequence switch S, the vertical. magnet operatingconduct-or 115. and vertical magnet 301 01 the otlice register OR tobattery. By the operation oi? vertical magnet 301, the wipers 304%307,inclusive, of the otlicc register (Ht are raised step by step and cometo rest opposite the desired level of bank contacts. Relay 101. Fig. 2is cnern I t, 7

gized in series with the vertical magnet and, being slow acting.maintz'iins its armature attracted throughout the. series out impulses.Upon energizing, relay 10.1 closes at armature 1.03 a circuit for theslow acting relay 102 which thereupon energizes and prepares at armature10 a circuit for stepping magnet 105 of the sequence switch S.

At the end 01? the series of impulses transmitted to the vertical magnetot the oti'ice register, slow acting series relay 1.01 dcenergizes andcloses'at armature 1.03 the circuit 01: stepping 111215;11011105 of thesequence switch S, whereupon the stepping magnet 105 energizes andadvances the wipers 108 and 109 into engagement with the second set ofbank contacts. A moment later, the slow acting relay 102, whose circuitis opened by armature 103, deenergizes and opens the circuit of magnet105 at armature 104.

The impulse distributing wiper 109 of the sequence switch S is now inengagement with the bank contact associated with the "otary magnet 302of the office register OR.

Accordingly, when the calling subscriber mai'iipulates his callingdevice in accordance with the second digit in the desired number, theresulting series oi impulses is trans mitted over the circuit abovetraced to the said wiper 109 of the sequence switch S and thence by wayof the second associated bank contact. and conductor 11.0 to rotarymagnet ing the sender in a manner to be pointed out hereinafter.

When. the first subscriber digit is dialled,

assumed, arethc contacts hang up prematurely.

the stepping magnet 401 of the first digit register DB Fig. 5, isoperated through wiper 109 of the sequence switch S, Fig. 2, and overconductor 121- and advances the wiper 40st into engagement "with thebank contact corresponding to the digit dialleifl. In the same way,responsive to the second, third, and fourth subscriber digits, the digitregisters DB DB and DB respectively, are operated overv conductors 122,123 and 12 1, respectively, and each advances its wiper into engagementwith the bank contact corresponding to the number of impulses received.I Returning now to the point at which wiper 108 of the sequence switch Sconnected up the interrupter 114 to the conductor 110, the steppingmagnet 231 of the sending switch 355 is thereafter operated tl'iroughthe resting contact and armature 213 under the control of interrupter114-. Upon the first ener- Zation of stepping magnet 231, theassociateci armature is attracted and moves the pawl into engagementwith the next notch in the wiper driving ratchet wheel. but does notmove the wipers 23-'l-23'7, inclusive. The armature of stepping magnet231 also opens the sending contacts 233., but the bridge acrossconductors 91 and 92 is not opened at this time owing to the fact thatthe contacts 232) are shunted at the resting contact and armature 208 ofpick-up relay 202. Upon the subsequent deenergization stepping magnet231, the wipers 234337. inclusive, are advanced into engagen'ientwiththe next set of bank contacts. \Vhen this occurs, wiper 255 openstheinitial circuit oii relay 205 which was formerly closed through wiper235 and the resting contact and armature 209, leaving relay 205 lockedup through armature 21S) and. its working contact. Accordingly, relay205 maintains the stopwipcr 236 which is the one to be used when thesender is started from the norn'ial position shown.) connected. withstop relay 203 at arn'iature 220. and maintains contact 238 in the bank011' wiper 234.- grounded at armature 2185-45) as toprevent wiper 23 1from losing ground. in case itrotates over contact 238 during thetransmission of the series of impulses.

As a further result ot the advance of the wipers of the sending switch,wiper 23 1 en a grounded contact, whereupon picle up .re lay 202energizes and removes at armature 208 the shunt from around contacts 233of the sending switch. Relay 202 also places an auxiliary ground onconductor 9 at armature 209 so to maintain the director busy until thesender has completed its operation in case the calling siiiloscrihershould It a further result of the energization of pick-up relay 202, icloses at armature 210 circuit over conductor 118 forthe steppingmagnet'lll loo the sequence switch S, whereupon stepping magnet 111energizes preparatory to advancing the associated wipers.

With the shunt removed from around the sending contacts 233 of thesending switch SS, each of the subsequent ene-rgizations of steppingmagnet 231 results in an opening of the bridgeacross conductors 91 and92, the wipers or the sending switch being advanced in the usual mannerupon each subsequent 'deenergization. Now, upon referring to Fig. wiper301 of the oilice register OR is in engagement with the bank contact308, which is cross-conneced on the intermediate distributing frame IDFby means of the jumper 312 to the third impulse stop conductor 3.Accordingly, the first code digit to be transmitted is the code digit 3,and, when three interruptions have been produced in the bridge acrossconductors 91 and 92, the stop wiper 236 of the sending switch isadvanced into engagement with the bank contact in which the thirdimpulse stop conductor 3 terminates, and stop relay 203 energizes overthe following circuit: From ground by way ofthe stop conductor controlwiper 113 of the sending control sequence switch S, Fig. 2, the firstassociated bank contact, the first code digit stop conductor 131, wiper30 of the oflice register OR, bank contact 308, jumper 312 of theintermediate distributing frame IDF, the third impulse stop conductor 3,the corresponding contact in the bank of wiper 236 of the sending switchSS, Fig. 3, armature 220 and its working contact, and stop relay 203 tobattery. Upon the closure of this circuit, stop relay 203 energizes andshunts the sending contacts 233 at armature 211, thereby terminating thetransmission of impulses. Relay 203 also opens the circuit 01' steppingmagnet 111 of the sequence switch S and closes a locking circuit foritself at arn'iature 21 1; shifts at armature 213 the circuit ofstepping magnet 231 from the interrupter lead 110 to wiper 23 1 throughthe interrupter contacts 232; and at armature 212 opens the lockingcircuit of relay 205. incidentally removing the ground potential frombank contact whereupon relay 205 deenergizes.

As a result of the opening of the circuit of stepping magnet 111 of thesequence switch S at armature 2141-, stepping magnet 111 deenergizes andadvances the wipers 113 and 114 into engagement with the second setoibank contacts, and as a result of the shifting of the circuit ofstepping magnet 231 of the sending switch SS at armature 213, steppingmagnet 231 is operated through wiper 234 and interrupter contacts 232and advances its wipers step by step until wiper 234 engages the bankcontact 238, which is at this time ungrounded. The wipers of the sendingswitch SS are now at their'intermediatenon 1 it *ill be noted that thefirst mal position and the circuit of pick-up relay 202 is open onaccount of the fact that wiper 23-1 is in engagement with an ungroundedbank contact. Relay 202, however, being slow acting, does not deenergizeimn'iediately.

In the selector D, Fig. 1, as a result of each of the threeinterruptions produced in the bridge across conductors 91 and 92 in thedirector, line relay 51 deenergizes and closes at armature 62 a circuitthrough armature 64 and its working contact and series relay 53 forvertical magnet 61. By the operation of vertical magnet 61, the wipers72-7 1, inclusive, are raised step by step and come to rest opposite thethird level of bank contacts. Relay 53 is energized in series withvertical magnet 61 and, being slow acting, maintains its armature 65attracted throughout the vertical movement. Upon the closure of the oilnormal contacts, a circuit is completed from the grounded release trunkconductor 13, through armature 65 and its working contact, and throughthe interrupter contacts 59 of rotary magnet 58 for stepping relay54,which thereupon energizes and closes alocking circuit for itself atarmature 66, and prepares a circuit for rotary magnet 58 at armature 67.

At the end of the vertical movement, the slow acting series relay 53deenergizes and completes the circuit of rotary magnet 58 at armature65, whereupon rotary magnet 58 energizes and advances the wipers 72*74,inclusive, into engagement with the first set of bank contacts in theselected level, and, near the end of its stroke, opens the circuit ofthe stepping relay 54; at its interrupter contacts 59. Stepping relay54L thereupon falls back and opens the circuit of rotary magnet-58 atarmature 67, whereupon rotary magnet 58 deenergizcs and closes itsinterrupter contacts 59 again.

From this point on, the operation depends upon whether the trunkterminating in the first set of bank contacts is busy or idle. If it isidle, switching relay 55 energizes, seizing the trunk. Assuming,however, that the trunk is busy, switching relay 55 is short circuitedby the ground potential encountered upon the busy test contact by testwiper 73, and stepping relay 5 1 energizes through test wiper 73 andagain completes the circuit of rotary magnet 58 at armature 67 whereuponrotary magnet 58 energizes alsoand advances the wipers into engagementwith the second set of bank contacts.

This alternate operation of stepping relay 54 and rotary magnet 58continues as described until an idle trunk is reached, which trunk, itmay be assumed, is the one comprising conductors 75;'Z7, inclusive. Whenthis idle trunk is reached, switching relay 55, being no longer shortcircuited, energizes from ground on the grounded release trunk conductor43 and in series with rial contacts 00, interrupter contacts 59, andstepping relay 54, but stepping relay 54 is not operatively energized atthis time on account of the high resistance of switching relay Uponenergizing, switching relay 55 opens the test circuit and prepares theusual holding circuit at arn'lature 69; disconnects ground from armature62 of the line relay 51 at armatiiu'e 70, thereby opening the circuit ofthe slow acting release relay 52; and at armatures 68 and 71 disconnectsconductors 42 and 44 from the windings of the line relay 51 and extendsthem by way of Wipers 72 and 74, the bank contacts with which they arein engagement, and conductors 75 and 77 to the line relay of theselector switch associated with the seized trunk. The line and releaserelays (not shown) of the seized selector now energize and the latterplaces ground on release trunk conductor 76, thereby grounding therelease trunk conductor 43 of the selector D through wiper 7 3 andarmature 69 and its working contact to maintain the holding circuitclosed nvi'terthe slow acting release relay 52 of the selector 1) hasdeenergized and also after the mleas-te relay 32 of the trunk circuitTChas deenergized, as it does subsequently.

in the director, the slow acting pick-up relay 202 falls back at the endof the interval for which it is adjusted and opens the circuit of slowacting stop relay 203 at armature 210. Stop relay 203 also maintainsitsarmature attracted. for an interval after its circuit is opened, at theend of which it will fall back and start the sender again as will\ bepointed out. The interval required for the relays 202 and 203 to fallback one after the other is made use ot by the selector D to pertorm theclnlinge-over and lll'tll'llirhlll'lliin g operations ELbOVt described.As a further resi'ilt oi the deeuergization of the slow actinn; pick-uprelay 202, it replaces ground on wiper of the sending switch SS,-therebycompleting a circuit through bank contact ior relay 204. Relay 204thereupon z-niergiacs and prepares a locking circuit for itself atarmature 216. and at armature 217 connects up the stop wiper 237 withthe stop relay 203. 1

At the end oi. the time for which it is adjusted, relay 203 deenergizesand closes at :u'mature 212 a locking circuit through the workingcontact and armature 216 for relay 204, at the same time connectingground through al'l'l'lfitllle 215 and its working contact to the firstcontact in the bank of wiper 234 so as to prevent the said wiper 234from losing ground in case it passes over such conta 5t (hiring thetransmission of the next (1 '11. As a further result of the deener-./ation of relay 203, it again connects stepping magnet 231 of thesequence switch SS to the interrupter 114, Fig. 2, through conductor110, thereby starting the sender-for gized through its locking circuitwhich in-- eludes armatures 212 and 216; closes a circu t at armature210 and over conductor 118 for thestepping magnet 111 of the sequenceswitch S; andat armature 208 removes the shunt from around the sendingcontacts 233 of the sending switch SS. Accordingly, upon each of thefollowing e'nergizations of stepping magnet 231, the bridge acrossconductors 91 and 92 is opened at the sending contacts 233. p v

I At the end of the fi fth interruption produced in the bridge acrossconductorslfll and 92 by stepping magnet 231 stepping magnet 231deenergizes and closes'the bridge again and; again advances the wipers234-237, inclusive Wiper 237, at this time engages the bank contact inwhich the fifth impulse stop conductor 5 terminates, thereby closing acircuit for stop relay 203 fol lows: From ground by way of stopconductor control wiper 113 of the sequence switch Si, Fig.2, the secondassociated bank contact, the second code digit stop conductor 132, wiper305 of the ofiice register OR, bank contact 309, jumper 313, the fifthimpulse stop conductor 5, the associated contacts in the bank of wiper237 of the switch SS, armature 217 and its working contact, and stoprelay 203 to battery. Upon energizing, stop relay 203 opens at armature214 the circuit of the stepping magnet 111 of the sequence switch S andcloses a locking circuit for itself; places a shunt around theinterrupter contacts 233 of the sending switch at armature 211; and atarmature 212 opens the locking circuit of relay 204. whereupon relzy 204deenergizes. As a further result of the energization of stop relay 203,it disconnects stepping magnet 231 from the interrupter lead at armature213 and connects it through the interrupter contacts 232 to thewiper'234. However, the wipers of the sending switch are not adicincedat this time, owing to the fact that they are now in one of their normalpositions, ground being removed from the first contact in the bank ofwiper 234.

Responsive to the transmission of the second code digit 5, the selectorswitch asse lit) lit

ciated with the trunk seized by the selector D, Fig. 1, operates in theusual manner to raise its wipers to the desired level and selccta trunkleading to the called oilice.

After the usual interval, relays 202 and 203 fallback one after theother to start the sender to transmit the next digit.

Returning now to the point at which the circuit of the stepping magnet111 of the sequence switch S was opened at the end of the second codedigit, stepping magnet 111, upon deenergizing, advances the wipers 113and 114 out of engagement with the second set of bank contacts and intoengagement with the third set, whereupon wiper 113 grounds the thirdcode digit stop conductor 133. Since only two code digits are needed totrunk the call to the desired office in this case, the third and fourthcontacts 310 and 311 in the set of contacts in use are cross-connectedby means of the jumpers 314 and 315, respcctively,to the skip conductor316. Accordingly, when the third code digit stop conductor 133 isgrounded by wiper 113, a circuit is closed through Wiper 306, bankcontacts 310, jumper 314, skip conductor 316, and the interrupter contacts 1 12for stepping magnet 111 of the sequence switch S, Whichthereupon energizes and interrupts its own circuit at contacts 112,whereupon it deenergizes and advances the wipers 113 and 114 anotherstep. Viper 113 at this time extendsground over the fourth code digitstop conductor 134 to the fourth office register wiper 307, and thenceby way of bank contact 311, jumper 315, and skip conductor 316 tostepping magnet 111 by way of interrupter contacts 112. Accordingly, thewipers 113 and 114 are automatically advanced another step and Wiper 113places ground upon the first subscriber digit stop conductor 141. v

When the sender is started the third time, as it following the usualinterval after the second digit, it transmits the first subscriberdigit. which is registered on the digit register DB This digit isterminated in the hereinbefore described manner wlicn wiper 236 of thesending switch SS arrives upon the impulse stop conductor upon whichwiper 404 of the digit register DB is standing. In case the firstsubscriber digit is 5 or under, thewipers of the sending switch SS arenot advanced beyond the intermedi ate normal position and thetransmission of the second subscriber digit commences with stop wiper237 connected-up by relay 204, but, if the first subscriber digit G orover, the wipers of the sending switch SS are rotated back to theinitial starting position and the transmission of the sec- .ondsubscriber digit starts with the stop wiper 236 connected up by relay205. At any rate, at the end of the first subscriber digit, the wipersof the sequence-switch S are advanced to ground the second subscriberdigit stop conductor 142 to terminate the second subscriber digit, asdetermined by the setting of the digit register DR In the same way, thewipers 113 and 114 of the sequence switclrS are advanced at the endof'the second subscriber digit, and ground is extended over the thirdsubscriber digit stop conductor 143 to the wiper of the third digitregister DR thereby terminating the third subscriber digit in the usualmanner, and, upon the advance of the wipers of the sequence switch S atthe end of the third subscriber digit, ground is extended over thefourth subscriber digit stop conductor 144 to the wipers of the fourthdigit register DB thereby terminating the fourth subscriber digit in theusual manner.

At the end of the transmission of fourth subscriber digit, the wipers113 114 of the sequence switch S are again vanced in the usual mannerand wiper 113 places ground upon conductor 94, thereliiy closing acircuit through the corresponding contact in the bank of wiper of thedirector selector DS, wiper 90, working contact and armature 86, andarmature and its working contact for switching relay 33 of the trunkcircuit TC. Switching relay 33 tl'iereupon energizes; closes a lockingcircuit for itself at arn'lature 40; and at a matures 39 and 41disconnects conductors 25 and 27froin the windings of line relay 31 andconnects them instead to conductors 42 and 44 extending to the selectorD, at the same time disconnecting the control bridge extending to thedirector, leaving the (25+ tablish'ed connection under the direct control of the calling line.

As; a result of line relay 31 of the trunk circuit TC being cut ofi', itdeenergizes and opens the circuit of release relay 32 at armr-u ture 34.Responsive to this release relay 32 deenergizes after a slight intervaland removes ground from rel-ease trunk coi. uctor 43 at armature 36,leaving the said release trunk conductor 43 grounded by way of therelease trunk conductor 76 of the trunk comprising conductors 75-77,inclusive.

As a further result of the deenergization of the release relay 32, itopens at arn'iature 37 the circuit of switching relay 81 of the directorselector D x'vh'ereupon switching relay 81 deenergizes and disconnectsthe wipers 8190, inclusive In the director, holding relay 201 nowdeenergizes andfplaces ground on the bank of wiper114 oft-he sequenceswitch S at armature 117, thereby closing a circuit throu ifh the lastcontact in the bank of wiper 114 for the stepping magnet 111, whereuponstepping magnet 11 1 energizes and opens its own circuit at contacts112, thereby deenergiziug and advancing the wipers 113 and 114 theremaining step to their normal po ition. As a further result of thedeenergization of the and for operating sa-id switch to count a train ofimpulses, and means i'or stopping said switch in one or the other of itsstarting positions depending on the number of impulses in the train.

G. In an impulse transmitter, a counting switch having a plurality ofstarting positions, means for operating said switch to count a train ofimpulses, means for rendering ine'ti'ective any starting positionreached during the counting of a train of impulses, and means responsiveto the completion of the transmission of said train of impulses forautomatically continuing the advance of said switch to its neareststarting position.

7. In an impulse transmitter, a counting switch having a plurality ofstarting posi tions, a plurality of test wipers in said switch, meansfor starting said switch from any position, and means for automaticallyrendering eli ective the particular test wiper which corresponds to theposition "from which the switch is started.

8. In a telephone sy tem, a progressively movable multi-position device"for counting a group of impulses, said device having a number of startpositions, Said number being greater than the number of positions on thedevice divided by the maximmn possible number of impulses in the group.

9. In'a telephone system, a progressively movable nmlti-position devicefor counting a group of impulses, said device having a number of startpositions, said number being greater than the number of positions on thedevice divided by the maximum possible number of impulses in the group,and means for causing any position on the device to correspond todifferent digits depending upon from which position the device startedin its counting action.

10. In a telephone system, a progressively movable n'iulti-positiondevice for counting impulses, and means for causing each position tocorrespond to any one of a plurality of dili'erent digits.

1.1. In a telephone system, a progressively movable multi-positiondevice for counting impulses, each position corresponding to a pluralityof different digits, said device having a plurality of start positions,and means depending upon from which position the device starts to fixthe digitcorresponding to each position of the device.

12. In a telephone system, a progressively movable device -tor countingimpulses, said device having a plurality of stop positions, and meansfor rendering ineffective any stop position reached before a count hasbeen completed.

13. In a telephone system, a progressively movable device for countingapredetermined number of impulses, said device having two stop positions,and means for rendering the first stop position to be reachedinefiective if the number of impulses is any amount greater than acertain amount.

14. In a telephone system, a progressive ly movable impulse transmitterwherein there is provided means for initiating the movement of thetransmitter to transmit a predetermined number or" impulse, and meanseffective when the impulses have been transmitted for continuing themovement of the transmitter until it reaches a stop position butrendering it ineffective to transmit additional impulses, characterizedin this, that the transmitter is provided with a plurality of stoppositions each of which may be reached during the impulse transmittingmovement of the transmitter, and means whereby those positions arerendered inetl'ective until the last named means has operated.

15. In a telephone system, an impulse transmitter including means fortransmitting impulses and a; counting switch for counting the impulsesas they are trans 'i'nitted, said counting switch having a plurality o'tnormal stopping positions, means for starting said counting switch fromany normal position at the beginning of the train of impulses, means foradvancing said switch beyond a succeeding normal position in case thenumber of in'ipulses is greater than a predetermined number, and meansfor stopping said counting switch at a succeeding position in case thenumber of impulses is not greater than that predetermined number.

16. In a telephone system, a counting device for counting groups ofimpulses, said device having a number of stop positions, means forrendering any stop position ineffective, and means for commencing countmfrom any of said stop positions.

17. In a telephone system, a counting device ior counting a group ofimpulses, said device having a number of stop positions, means dependentupon the number of impulses counted lior determining in which positionthe switch will stop, and means for commencing the subsequent operationof the switch from the preceding stop position.

18. In a telephone system, a device for counting a number of impulses,said device having two stop positions, and means for stopping saiddevice in one of said positions if the number of impulses counted is notmore than a certain number and in the other position if it is more thansaid number.

19. In a telephone'system, a progressively movable multi-position devicefor transmitting impulses, and means for rendering any one of certain ofthe positions a stop position depending upon which position was the laststop position and the number of impulses that are transmitted.

In witness whereof, I hereunto subscribe my name this 6th day of June,A. D. 1924.

RUDOLPH F. STEHLIK.

Inn

